The investment is on the top of Rs 25,000-crore spending the Group had announced on the first day of Vibrant Gujarat Summit here.

"We are going to continue our investments in port sector. We will invest another Rs 20,000 crore over the next 5 years to add another 100 million tons capacity in Gujarat," he said at the Summit on Sunday.

Adani Ports & Special Economic Zone (APSEZ) - a part of the Adani Group - is India's largest multi-port operator. It operates six ports in the country including four in Gujarat - Kandla, Mundra, Hazira and Dahej. The ports handled a total cargo of 112.8 million tons in 2014.

"We are signing exclusive MoU with Port of Rotterdam to jointly identify and attract port-based industries in Gujarat," Adani said. "We are aggressively expanding our activities in Gujarat and globally."

Adani said his group had on Sunday signed an MoU with US-based SunEdison to invest Rs 25,000 crore in a solar manufacturing complex to produce 27,000 metric tons of poly-silicon and 2000 MW capacity equivalent of crystals. "This will be the largest integrated solar manufacturing facility in the world."

Also, Adani has signed an MoU with Australia's largest independent oil and gas company Woodside Energy for "a strategic alliance within the energy value chain," he said.

Adani and SunEdison will establish a joint venture for building the largest vertically integrated solar photovoltaic manufacturing facility in the country.

The joint venture will build the solar facility with an investment of around USD 4 billion (around Rs 25,000 crore), Adani said.

"India has embarked on an ambitious programme to become a world leader in power generation from renewable technologies, and sees solar as a key part in realising that goal," Adani Power CEO Vneet S Jaain said.

Adani on Sunday signed an MoU with Australian energy major Woodside for sourcing of LNG as well as cooperation in oil and gas exploration and production.

"The two companies will jointly explore opportunities in sourcing of liquefied natural gas (LNG), supply and purchase arrangements for India, LNG marketing, investment in upstream activities such as oil and gas exploration, production and liquefaction plants, knowledge sharing, training, joint technology studies, technology workshops and connecting local R&D institutions and universities with each other," the company had said on Sunday.